Captain Carter frowned and began to pace around the small laboratory. "Speculate," he ordered. "What were those people doing there? Why would they all be interred in that spot?"
"They're human," Doctor Faust said, rubbing the bags beneath his eyes with knobby fingers. "I've made every measurement and run every test that I can, and nothing I've seen has given me reason to think that they could be something else."
Lamont, Francis and Phobos had joined the doctor in the medical bay's laboratory. They were standing around a metal tray on which the specimens that they had managed to carefully transport from the moon's surface were carefully laid out: The cracked dome of a cranium, a jaw, a few finger bones and such. It had been no small feat to obtain that much. The remains, preserved in some kind of delicate equilibrium by the deep pool of liquid oxygen, were liable to crumble into dust at the slightest touch when the pool was drained.
It occurred to Lamont, as he gazed at the bones, that the oxygen which had served as a graveyard for these people was likely now, as they spoke, being circulated around the ship. He shuddered.
"Not Martian, then?" Francis ventured, rubbing his jaw. Uncharacteristically, his long face was lightly stubbled with white whiskers. Lamont wondered if he had neglected to shave in his eagerness to hear the doctor's verdict.
"Certainly not," Phobos answered, preempting Faust, who closed his mouth and nodded in agreement.
"Do you have any idea how long the bodies have been there?" Lamont asked.
Faust shrugged. "Given the temperature of the oxygen and the trace minerals contained in it, the soft organic material would have broken down quite quickly. After that, the bones will have been preserved indefinitely unless disturbed by an outside force. As far as I know, it could be 50 years, or 50,000."
Captain Carter frowned and began to pace around the small laboratory, his gaunt profile reflecting in weirdly distorted caricatures among the glass bulbs and tubes of chemical and electronic equipment. "Speculate," he ordered. "What were those people doing there? Why would they all be interred in that spot?"
"The natural theory would be that they were involved in the construction of the tower," Phobos posited. "Perhaps there was some kind of accident or disaster and removing them from that spot was impracticable."
The doctor's clever eyes regarded Phobos with an expression that Lamont interpreted as incredulity. "But it's highly unlikely that the crater in which they were found was the site of the disaster."
"A good point," Phobos agreed. "There is no time in the surmised geographical history of the moon during which a protective suit would not have been required on its surface. Metal components may have dissolved in the oxygen over time, but it is almost certain that some inorganic artifacts would have been found among the bones. As far as we could tell, there were none."
"So those people were, what?" Lamont asked, gazing at the bones. "Naked?"
"For all practical purposes, given the lack of other evidence," Phobos confirmed.
"Like a mass grave," Faust said darkly. "I've seen some of those in my time. This fits the type."